Abstract
In order to exploit mean-reverting behavior among the price differential between two markets, one can use unit root tests to determine which pairs of assets appear to exhibit mean-reverting behavior. Since nonlinear mean reversion shares the same meaning as local stationarity, this paper proposes a Bayesian hypothesis testing to detect the presence of a local unit root in the mean equation using Markov switching GARCH models. This model incorporates a fat-tailed error distribution to analyze asymmetric effects on both the conditional mean and conditional volatility of financial time series. To implement the test, we propose a numerical approximation of the marginal likelihoods to posterior odds by using an adaptive Markov Chain Monte Carlo scheme. Our simulation study demonstrates that the approximate Bayesian test performs properly. The proposed method utilizes the daily basis between the FTSE 100 Index and Index Futures as an illustration.
Similar content being viewed by others
References
Alizadeh AH, Nomikos N (2004) A Markov regime switching approach for hedging stock indices. J Futures Mark 24:649–674
Alizadeh AH, Nomikos NK, Pouliasis PK (2008) A Markov regime switching approach for hedging energy commodities. J Bank Finance 32:1970–1983
Ang A, Bekaert G (2002) Regime switches in interest rates. J Bus Econ Stat 20:163–182
Bauwens L, Preminger A, Rombouts JV (2010) Theory and inference for a Markov switching GARCH model. Econom J 13:218–244
Bauwens L, Rombouts JVK (2007) Bayesian clustering of many GARCH models. Econom Rev 26:365–386
Berger JO, Delampady M (1987) Testing precise hypotheses. Stat Sci 2:317–335
Bollerslev T (1986) Generalized autoregressive conditional heteroskedasticity. J Econom 31:307–327
Bollerslev T, Chou RY, Kroner KF (1992) ARCH modeling in finance: a review of the theory and empirical evidence. J Econom 52:5–59
Carlin BP, Chib S (1995) Bayesian model choice via Markov chain Monte Carlo methods. J R Stat Soc Ser B 57:473–484
Carlin BP, Polson NG, David S Stofer DS (1992) Monte Carlo approach to nonnormal and nonlinear state-space modeling. J Am Stat Assoc 87:493–500
Chen CWS, Lee S (2015) A local unit root test in mean for financial time series. J Stat Comput Simul. doi:10.1080/00949655.2015.1037765
Chen CWS, Chen SY, Lee S (2013) Bayesian unit root test in double threshold heteroskedastic models. Comput Econ 42:471–490
Chen CWS, Gerlach R, Choy STB, Lin C (2010) Estimation and inference for exponential smooth transition nonlinear volatility models. J Stat Plan Inference 140:719–733
Chen CWS, So MKP (2006) On a threshold heteroscedastic model. Int J Forecast 22:73–89
Chen CWS, So MKP, Lin EMH (2009) Volatility forecasting with double Markov switching GARCH models. J Forecast 28:681–697
Chib S (1995) Marginal likelihood from the Gibbs output. J Am Stat Assoc 90:1313–1321
Chib S, Ramamurthy S (2014) DSGE models with student-t errors. Econom Rev 33:152–171
Dickey DA, Fuller WA (1979) Distribution of the estimators for autoregressive time series with a unit root. J Am Stat Assoc 74:427–431
Deschamps PJ (2008) Comparing smooth transition and Markov switching autoregressive models of US unemployment. J Appl Econom 23:435–462
Engle R (1982) Autoregressive conditional Heteroskedasticity with estimates of the variance of United Kingdom inflation. Econometrica 50:987–1007
Francq C, Zakoïan JM (2001) Stationarity of multivariate Markov-switching ARMA models. J Econom 102:339–364
Früuhwirth-Schnatter S (2001) Markov chain Monte Carlo estimation of classical and dynamic switching and mixture models. J Am Stat Assoc 96:194–209
Früuhwirth-Schnatter S (2006) Finite mixture and Markov switching models. Springer, New York
Gelfand AE, Dey DK (1994) Bayesian model choice: asymptotic and exact calculations. J R Stat Soc Ser B 56:501–514
Gelman A, Roberts GO, Gilks WR (1996) Efficient metropolis jumping rules. In: Bernardo JM, Berger JO, Dawid AP, Smith AFM (eds) Bayesian statistics 5. Oxford University Press, Oxford, pp 599–607
George EI, McCulloch RE (1997) Approaches for Bayesian variable selection. Stat Sin 7:339–373
Gerlach R, Chen CWS (2008) Bayesian inference and model comparison for asymmetric smooth transition heteroskedastic models. Stat Comput 18:391–408
Geweke J (1996) Variable selection and model comparison in regression. In: Bernardo JM, Berger JO, Dawid AP, Smith AFM (eds) Bayesian statistics 5. Oxford University Press, Oxford, pp 609–620
Hall SG, Psaradakis Z, Sola M (1999) Detecting periodically collapsing bubbles: a Markov-switching unit root test. J App Econom 14:143–154
Hamilton JD (1989) A new approach to the economic analysis of nonstationary time series subject to changes in regime. Econometrica 57:357–384
Jacquier E, Polson NG, Rossi PE (1994) Bayesian analysis of stochastic volatility models. J Bus Econ Stat 12:371–389
Jeffreys H (1961) Theory of probability, 3rd edn. Oxford University Press, Oxford
Koop G, Steel MFJ (1994) A decision-theoretic analysis of the unit-root hypothesis using mixtures of elliptical models. J Bus Econ Stat 12:95–107
Kwiatkowski D, Phillips PCB, Schmidt P, Shin Y (1992) Testing the null hypothesis of stationarity against the alternative of a unit root. J Econom 54:159–178
Li Y, Yu J (2010) A new Bayesian unit root test in stochastic volatility models. In: Research collection school of economics paper, vol 1240. Singapore Management University
Lubrano M (1995) Testing for unit roots in a Bayesian framework. J Econom 69:81–109
Marriott J, Newbold P (2000) The strength of evidence for unit autoregressive roots and structural breaks: a Bayesian perspective. J Econom 98:1–25
Monoyios M, Sarno L (2002) Mean reversion in stock index futures markets: a nonlinear analysis. J Futures Mark 22:285–314
Nelson CR, Piger J, Zivot E (2001) Markov regime switching and unit-root tests. J Bus Econ Stat 19:404–415
Newton MA, Raftery AE (1994) Approximate Bayesian inference by the weighted likelihood bootstrap (with discussion). J R Stat Soc Ser B 56:3–48
Phillips PCB (1991) Bayesian routes and unit roots: de rebus prioribus semper est disputandum. J App Econom 6:435–474
Phillips PCB, Perron P (1988) Testing for unit roots in time series regression. Biometrika 75:335–346
Said SE, Dickey DA (1984) Testing for unit roots in autoregressive-moving average models of unknown order. Biometrika 71:599–607
Sarno L, Valente G (2000) The cost of carry model and regime shifts in stock index futures markets: an empirical investigation. J Futures Mark 20:603–624
Schotman P, van Dijk HK (1991) A Bayesian analysis of the unit root in real exchange rates. J Econom 49:195–238
Sims CA (1988) Bayesian scepticism on unit root econometrics. J Econ Dyn Control 12:463–474
Tanner MA, Wong WH (1987) The calculation of posterior distributions by data augmentation. J Am Stat Assoc 82:528–540
Triantafyllopoulos K, Montana G (2011) Dynamic modeling of mean-reverting spreads for statistical arbitrage. Comput Manag Sci 8:23–49
Vosseler A (2014) Bayesian model selection for unit root testing with multiple structural breaks. Comput Stat Data Anal. doi:10.1016/j.csda.2014.08.016
Zhang JY, Li Y, Chen ZM (2013) Unit root hypothesis in the presence of stochastic volatility, a Bayesian analysis. Comput Econ 41:89–100
Zivot E, Phillips PCB (1994) A Bayesian analysis of trend determination in economic time series. Econom Rev 13:291–336
Acknowledgments
We thank the AE and referees very much for their time and careful, extensive comments on our paper, which have led to an improved version of it. Cathy W.S. Chen’s research is funded by the Ministry of Science and Technology, Taiwan (NSC 101-2118-M-035-006-MY2, MOST 103-2118-M-035-002-MY2). Sangyeol Lee’s research is supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Science, ICT and future Planning (No. 2015R1A2A2A010003894).
Author information
Authors and Affiliations
Corresponding author
Appendix: MCMC sampling scheme
Appendix: MCMC sampling scheme
The MCMC sampler consists of simulating each parameter group from its full conditional posterior discussed in Sect. 3. The symbol k on a parameter denotes a draw of the parameter at the kth iteration of the algorithm. We randomly select the initial value of the state vector \({\varvec{S}}\) from a first-order Markov process assuming values in \(\{1, 2\}\). We set the initial values for all parameters, i.e. \(k =0\). One iteration of the algorithm involves the following steps:
- Step 1: :
-
Sample \({\varvec{\phi }}_i|{\varvec{y}},{\varvec{\delta }}, {\varvec{S}}, {\varvec{\theta }}_{-{\varvec{\phi }}_i}\) from its posterior in (12). Check the constraint that \({\phi }_1^{(1)} \ge {\phi }_1^{(2)}\). If this constraint is not satisfied, then we relabel the draws \(({\varvec{\phi }}_1,{\varvec{\phi }}_2)\).
- Step 2: :
-
Sample \(\delta ^{(i)}\) from a Bernoulli distribution with success probability in (14). Count the number \(I(\delta ^{(i)}=1)\), \(i=1, 2\).
- Step 3: :
-
Sample \(s_t| {\varvec{y}},{\varvec{\delta }},{\varvec{S}}_{-t},{\varvec{\theta }}\), \(t=2, \ldots , T\) from its posterior in (14).
- Step 4: :
-
Sample \(p_{ii}| {\varvec{y}}, {\varvec{\delta }},{\varvec{S}}, {\varvec{\theta }}_{-p_{ii}}\) from its posterior in (18).
- Step 5: :
-
Sample \({\varvec{\alpha }}_i|{\varvec{y}}, {\varvec{\delta }},{\varvec{S}}, {\varvec{\theta }}_{-{\varvec{\alpha }}_i};\) from its posterior in (19).
- Step 6: :
-
Sample \(\nu | {\varvec{y}}, {\varvec{\delta }},{\varvec{S}}, {\varvec{\theta }}_{-\nu }\) from its posterior.
- Step 7: :
-
\(k=k+1\) and go to Step 1.
These steps are repeated until \(k=N\) so that the convergence of the Markov chain is achieved, and we calculate the posterior median \(\tilde{{\varvec{\theta }}}\). The first term of Eq. (8) is the log-likelihood evaluated at \(\tilde{{\varvec{\theta }}}\). We determine the mean of \(\pi _i\) (denoted by \(\tilde{\pi }_i\)) from Step 2, which is used to compute the prior odds ratio \(\tilde{\pi }_i/(1-\tilde{\pi }_i)\). The value of \(\text{ POR }= \text{ BF }\times \tilde{\pi }_i/(1-\tilde{\pi }_i)\) to test the unit root hypotheses is then obtained.
Rights and permissions
About this article
Cite this article
Chen, C.W.S., Lee, S. & Chen, SY. Local non-stationarity test in mean for Markov switching GARCH models: an approximate Bayesian approach. Comput Stat 31, 1–24 (2016). https://doi.org/10.1007/s00180-015-0624-4
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00180-015-0624-4